The present disclosure relates to a functional device using, for example, MEMS (Micro Electro Mechanical Systems) technology, and an acceleration sensor and a switch each of which uses such a functional device.
MEMS have attracted attention as elemental technology to achieve downsizing and high functionality in semiconductor devices such as acceleration sensors and high-frequency switches. The MEMS are a system configured by mixing a micro-mechanical element and an electronic circuit element by silicon process technology. When an external impact force is applied to the MEMS, a movable section of the MEMS is damaged by a stress to cause mechanical breakdown. In consideration of this, a device configuration using a so-called mechanical stopper has been proposed (for example, Japanese Unexamined Patent Application Publication (Published Japanese Translation of PCT Application) No. 2012-528305).